More radiation monitoring problems found at Vt. Yankee

BRATTLEBORO, Vt. — The Vermont Yankee nuclear plant had two more malfunctions of its radiation monitors on the plant’s refueling floor last week, for a total of four erroneous readings that radiation had exceeded safe standards within the building.

Darren Springer, deputy commissioner of the Department of Public Safety, said Monday the monitors failed to work properly last Tuesday and Wednesday, and reinforced the state’s concern that more information from the Nuclear Regulatory Commission was needed.

So far, only malfunctions on June 14 and July 11 have been reported to the public by the NRC. Entergy reported only two malfunctions in its formal report to the NRC on Friday.

“We’ve heard of other incidents,” Springer said Monday.

Springer said Uldis Vanags, the state nuclear engineer, had been at Vermont Yankee on Wednesday and learned of the incidents.

Entergy Nuclear spokesman Robert Williams confirmed Monday that there were four problems with the radiation monitors — one in June and three in July.

He said four monitors, two on the refueling floor and two in the plant ventilation system, were changed. He said the monitors were changed Wednesday.

“They are designed to monitor for elevated radiation levels and if necessary, to automatically realign the plant ventilation system,” Williams said. He said the plant treated all four incidents as “real alarms” and followed plant procedures.

He said a technician used a portable radiation monitor to verify there were no elevated levels.

He said the failed monitors had been changed last year, and he said typically radiation monitors are changed every six or seven years.

“The manufacturer indicated to us that they had seen other similar issues and that contributed to the decision to change them out,” he said.

Neil Sheehan, a spokesman for the NRC, said he was not aware of similar problems with radiation monitors at other nuclear facilities, and said he wasn’t sure the Yankee monitors had been changed.

“They have multiple radiation monitors,” Sheehan said, saying the monitors were “malfunctioning rather than broken.”

Springer said the state had already heard from the NRC Monday after the state’s concerns about the lack of information about the radiation monitor problems, and that the NRC was setting up a conference call later in the week for the state to have its questions answered. He said the state also requested a response in writing by NRC Region One administrator William Dean.

“We expect to get a full accounting,” said Springer, who said that the state rejected Entergy’s claim that the monitors hadn’t “failed,” but simply had a “spurious spike.”

“Common sense would indicate that when an operating safety system is registering a false reading, I think it’s appropriate to say they failed. It’s not really an issue of semantics, but it’s not working properly,” said Springer.

The state is also concerned that the NRC only has a 60-day reporting requirement for the radiation monitor problems.

He said Entergy had conducted “trouble-shooting” June 14, and repaired a loose connection “they believed was the cause.”

But on July 11, there was another spike in radiation on the monitor, and the company suspected “electrical noise” or static, he said.

Springer said he believed such problems should be reported promptly, and in full detail.

Raymond Shadis, senior technical adviser for the New England Coalition, an anti-nuclear group, said he believed Entergy was releasing information on the radiation monitor problem bit by bit, which he said was never a good sign.

“There is a long tradition of letting out bad news piecemeal,” he said, citing Entergy’s history with its collapsed cooling tower, and the tritium leak in 2010.

Shadis said he suspected that there were “serious contamination issues” at the plant, but if one accepts Entergy’s explanation of “stray electrical impulses” setting off the monitors, that was hardly reassuring.

“It’s upsetting their safety-related equipment, and neither is good news,” he said.